


Dessert

by ecto_zone



Category: Undertale (Video Game)
Genre: Blue is a powerbottom, Cuntboy, Dirty Talk, Fluff, Incest, M/M, Papyrus is goofy, They're both incredibly horny though
Language: English
Status: Completed
Published: 2018-05-21
Updated: 2018-05-21
Packaged: 2019-05-09 17:01:08
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,026
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14720064
Author URL: https://archiveofourown.org/users/ecto_zone/pseuds/ecto_zone
Summary: The Swaps are in town, Papyrus is excited about it. Little does he know, Blue has his own itinerary for the evening.





	Dessert

**Author's Note:**

  * For [Sinfulpinku](https://archiveofourown.org/gifts?recipient=Sinfulpinku).



“You know, I really wish you would pick up your sock. We have company coming over!”

 

Papyrus whirled about the main room of the brothers’ home. Although he was already dutiful about ensuring that his nigh-impeccable standards of order and cleanliness were met in day-to-day life, the mention of having company besides his beloved Captain had kicked him into overdrive. His determination to make the house completely spotless was further amplified by the aforementioned visitors being none other than an alternate version of themselves - who they had long since begun nicknaming “Stretch” for Papyrus and “Blue” for Sans, respectively. In Papyrus’s mind, he knew that no other monster would have a better idea of how unkempt their home could be than themselves, which meant that he had to ensure that everything was spotless!

 

Sans didn’t seem too interested in his brother’s initiative.

 

“Hey, it wouldn’t be home without it.” Sans shrugged, shifting on the sofa as he reclined. He moved to put the bottle of ketchup he held onto the table, shocked to see a coaster skid across the table, landing right under where he was planning on setting his bottle down.

 

“Jeez, you’re not gonna let me coast by with my usual habits today, are you?” Sans glanced over at his brother, who returned his glance with an eye roll and a smirk. “Not in the slightest! I’ve been looking forward to this for weeks, and I’m not going to let you turn our picturesque abode into a trash dump!”

 

“Heh, far be it from me to get in the way, then.” Sans swung his legs around to rest them on the coffee table, only for Papyrus to swing the table forward, just out of Sans’s reach.

  
“I literally _just_ wiped that down, don’t even think about getting your ratty sneakers on our coffee table!”

 

“Bro, we don’t even drink coffee.”

 

Papyrus was about to say something, but stopped short as Sans’s words started to sink in. He put a gloved finger up to his chin, clearly overthinking such a mundane quirk of language. Sans, realizing he was being little more than a nuisance, decided now was the best time to make himself scarce. Company or no, he had a very tight schedule of loitering to adhere to.

 

Sans slumped off the sofa, shuffling his way towards the door. “Well, speaking of drinks, I think it’d be best if I got outta your hair to let you finish cleaning the place up.”

 

Papyrus snapped back to attention, reaching a hand out halfway before retracting it. “Sans... Well, alright, but I expect you to get back here before they arrive. I’m not going to let you skip out on this.”

 

Sans chuckled, his hand already on the doorknob. “What, me? Avoiding people? Perish the thought-”

 

Sans opened the door, finding himself staring face-to-face with the alternate version of himself, his gloved fist hanging in the air mid-knock.

 

“Oh, hey.” Sans said, raising a hand in greeting. “Hey pap, we’re here.”

 

Papyrus looked up from the shelf he was dusting. “What do you mean, Sans, of course we- OH MY GOD, WE’RE HERE- I MEAN, THEY- FOR GOODNESS SAKE, SANS!”

 

Papyrus gave Sans a quick shove so that he was just outside the doorway, pressed up against Blue. Papyrus looked at the assembly, his face red. He held up a finger. “One moment, please!”

 

The door slammed behind him. The sounds of a great calamity erupted from inside as Papyrus pushed himself even further beyond, cleaning like no skeleton had ever cleaned before.   
  
As the chaos unfolded inside, Sans sidled around Blue, nudging Stretch on the side. “Welp, I was about to head over to Grillby’s. Wanna come with?’

 

Stretch shrugged. “Eh, sure.” He looked over at his brother. “Blue, we’ll be back in a bit. Don’t get into any trouble, alright?”

 

Blue gave his brother a quick salute, a tiny cyan star shooting behind his head as he did so. “Sure thing, Pappy!”

 

Stretch gave his brother a nod before turning around, digging into his coat pocket. He pulled out a pack of cigarettes, taking one into his hand and placing it in his mouth. The cigarette was set alight with a snap of Stretch’s fingers, sending a thin trail of smoke into the air and a wave of menthol into his non-existent lungs.

 

Stretch shook another cigarette out and held it in Sans’s direction. He declined, holding up a hand. “Nah, I’m tryin’ to cut back.”

 

Stretch chuckled. “I didn’t know you started.”

 

The pair departed, leaving Blue alone on the doorstep.

 

Stretch turned back to Blue as he and Sans entered Grillby’s. Blue gave his brother a wave, and Stretch returned the gesture with a wink before following after Sans.

 

Blue was ecstatic - little did Sans know that Stretch was going to be the distraction all along! Blue thanked his lucky stars for this auspicious turn of events - he had wracked his brain all night trying to figure out how to get himself alone with Papyrus, and it ended up happening all on its own! Whether this was fate or just dumb luck, Blue was determined not to miss his chance.

 

With a flourish of his hand, Blue knocked on the door, the noise from the inside having calmed down. The door swung open, Papyrus beaming down at Blue.

 

“Welcome! Please, come on in, my esteemed…!”

 

Papyrus’s sentence hung in the air as he realized the waiting congregation had lost two thirds of its members.

 

“...Guest.”

 

Blue leaped onto Papyrus, latching his arms around the sentry’s battle body.

  
“Papyrus~!”

 

Papyrus, recovering from his momentary surprise, returned the gesture, cradling Blue with his free hand and patting him on the back.

  
“Blue, it’s so good to see you again!”

 

Papyrus looked around a bit. “If you don’t mind me asking… Where did your brother go?”

 

Blue looked up at Papyrus. “Oh, Stretch? He ran off with Sans. They’re at Grillby’s now!”

 

Papyrus sighed. “Another casualty to the morass of grease and dog hair.”

 

Blue giggled, nestling his head against Papyrus’s chestplate.

 

Papyrus sighed. “Well, at least Sans is being sociable like I asked.”

 

Blue leaned back, placing his hands on Papyrus’s shoulders. “Guess it’s just you and me tonight!”

 

Papyrus’s cheeks flushed for a moment before shutting his eyes, releasing his grip on the door to rub the back of his neck. “Nyeh heh heh, I guess it is!”

 

Papyrus kicked the door behind him, twirling around and setting Blue down.

 

“Make yourself at home! I believe you will find I have whipped this place into pristine condition!”

 

Blue made his way around the room, awestruck at the spotless interior. The level of cleanliness rivaled - no, surpassed his own! He poured every nook and cranny, each individual problem spot - where Pappy liked to drop his cigarette butts when he smoked in the house, that one  spot behind the couch that was impossible to reach, even the pet rock’s sand bed!

 

“Stars…” Blue began, gawking in amazement. His pupils shone as bright neon stars.

 

Papyrus’s cheeks lit up in response, pride welling up from within him. He placed a hand on his chest as his scarf began to flap. “Why thank you, my diminutive friend! I pride myself in having the cleanest home in all of Snowdin!”

 

“I can tell!” Blue giggled.

 

Papyrus cleared his throat, his cheeks flaring scarlet before subsiding.

 

“Well, erm… Please make yourself at home! All of our amenities are yours to use, and when you’re ready for dinner, I would be happy to make you whatever you would like!”

 

At that moment, Papyrus’s eye sockets bulged, the colors within inverting, giving them the appearance of real eyes. Papyrus realized, much to his chagrin, that he had forgotten to go grocery shopping, and the cabinets were bare beyond the usual spaghetti ingredients. He wasn’t even fond of the pasta, he just wanted to master his first dish before moving on to greater challenges, and it was always economic to buy in bulk! It seemed now that his economic prudence had caused a dire consequence of limiting his ability to be a good host.

 

Papyrus hid his mouth behind his gloved hand, beads of sweat forming. His eyes darted around, and his mind raced for a solution. Inspiration struck, and he spoke up.

 

“...As long as it’s spaghetti!”

 

Papyrus hated to attempt to strongarm his guest, but it was in dire times like these that he had to rely on his force of personality to save face. Only someone as confident as Papyrus could play such a gambit - at least, that’s what he told himself.

 

Blue cocked his head, confused for a moment before returning to his polite smile. “Oh, of course! I’d love to try whatever you feel like making!”

 

Papyrus sighed as a wave of relief swept through him. Blue leapt onto the couch, the springs groaning in unison as he bounced on the lumpy cushions. He leaned over and pat the empty cushion, looking at Papyrus.

 

“But first, I think it would be nice to catch up, don’t you? C’mon, take a seat!” He clasped his hands on top of each other and laid them on his lap. “I don’t bite!”

 

“Nyeh heh heh… Of course! I am interested in learning about your reality, and I am sure you are curious about ours!”

 

Papyrus took a seat next to Blue, jostling around for a comfortable position. Blue scooted closer, focusing his gaze on Papyrus’s face.

 

“Soooooo~” Blue began, “What has the Great Papyrus been up to lately?”

 

Papyrus returned Blue’s gaze with a smile, kicking back on the sofa and adopting his coolest reclining pose. He spoke at length about his various puzzles and assorted schemes to best a human, should one ever dare to tread within the jurisdiction of his sentry station. He then went on to describe, in great detail, his training regimen with Undyne, along with his aspiration to become a Royal Guard himself. Blue hung on every word, relating to Papyrus’s plights and feeling sympathetic towards his fears and doubts. After all, they were very similar.

 

Time flew by, and before either of them knew it, several hours had passed. During a lull in the conversation, Blue began to realize that, beyond the butterflies in his stomach, a dull ache was building.

 

“Papyrus?” Blue interrupted, as Papyrus scanned his mind for the name of a pasta that eluded him.

 

“Lan… Langini? No- Oh, what is it, Blue?” Papyrus snapped to attention.

 

“Could we make dinner now? All this pasta talk is making me hungry!”

 

Papyrus stood up. “Of course! Come, my friend, you can be my assistant!”

 

Papyrus reached a hand towards Blue, inviting him to take it. Blue took Papyrus’s hand, face flushed once more, and was assisted off the couch. They made their way to the kitchen, and Papyrus began to retrieve the necessary components of the evening’s meal.

 

Papyrus began by filling up a pot with water, and then turned the oven to the appropriate temperature. Blue spectated as Papyrus studied the water for the perfect moment to insert the dry noodles.

 

As Blue watched from the sidelines, Papyrus’s focus on dinner left him without a companion to talk to. Blue was left alone with his thoughts, and his mind, now unrestrained, began to wonder.

 

“Blue, could you hand me the sauce?”

 

Blue stared at Papyrus, eyes fluttering as he drank in all the fine details of his lanky yet imposing figure. His eye sockets were such a consuming yet comforting shade of black, he felt as if he could get lost in them-

 

“Blue, the sauce?”

 

-and that voice! So crisp and formal! He wished to have a voice like his, one that could command respect just as easily as it could charm a dignitary. So smooth, so refined-

 

“Where’s the spaghetti sauce?!”

 

Blue let out a soft gasp, Papyrus’s shout knocking him out of his daydream. Without looking down, Blue grabbed at something and pushed it towards him, maintaining his gaze on Papyrus. Blue sighed, allowing his chin to rest on his knuckles once more as he settled back into his daydream.

 

“Blue?”

 

Ah, his spine shuddered whenever he said his name! Sure, people called him by his pet name all the time, but none of them had the same sing-song canter that Papyrus had-

 

“This is paprika. I need the sauce.”

 

Blue murmured, too distracted to correct his error. “Mm, my bad.” He slid something else over without breaking his gaze..

 

Papyrus scoffed. “Tuna, Blue? Is this a jo-“ Papyrus turned to Blue, only now noticing where Blue’s attention lied. 

 

“Oh…”

 

Papyrus’s cheeks reddened. He wasn’t sure if he should feel off-put or flattered by the intensity of Blue’s stare. 

 

“ _ But, surely he couldn’t possibly…”  _

 

Papyrus’s internal monologue began before he cleared his throat, deciding to address the situation.

 

“Nyeh heh, I see you’ve become enraptured by my dashing good looks!” Papyrus smiled at Blue. Blue remained silent, but the cyan blush on his face intensified into a neon turquoise.

 

He wasn’t used to such ardent admiration.

 

“Heheh, I suppose I am pretty great, aren’t I?” Papyrus looked to Blue for a response.

 

“You’re just so… You’re so happy, and energetic! You’re sweet and charming, confident…” Blue’s words dripped with longing.

 

“W-why thank you, Blue! You are very kind, yourself! And hard-working! And…”

 

Papyrus’s words slowed as his gaze began to settle on Blue.

 

“You’re as kind and caring as I’ve always wanted to be...”

 

Blue picked up where Papyrus left off. “And you’re as dashing and graceful as I’ve wanted to be...”

 

Papyrus lifted a hand towards Blue’s cheek, Blue drawing closer as Papyrus leaned in.

 

Their faces were separated by mere millimeters when the sound of boiling water filled their ears. Papyrus looked to his left, watching the rolling boil of the pot water.

 

Papyrus leaned over the stove and clicked the knobs off. He returned his attention to Blue.

 

“So, uh, were we going to-” Papyrus started, and was then interrupted by Blue as he yanked on the front of his scarf, pulling Papyrus downwards at face level. Blue wasted no time in grasping Papyrus’s cheeks in his hands, pulling him in so that their mouths locked.

 

“Mmph-!” Papyrus let out as Blue held their faces together, locked in a kiss. By degrees, Papyrus’s shock faded, and he moved his hands to Blue’s sides. Papyrus’s back straightened, grasping Blue by his waist, lifting him off the ground as one hand moved to cradle him by his rear.

 

Blue pulled himself away, his chest heaving as he caught his breath.

 

Papyrus’s confidence surged.

  
“So… My room?” Papyrus petitioned.

 

Blue gave an enthusiastic nod, and Papyrus bolted out of the kitchen, Blue in his arms.

 

Having been pent up for hours now, Blue wasn’t in the mood to wait another moment. Even as Papyrus carried him up the stairs, Blue teased at Papyrus’s groin with a hand as he used the other to steady himself on his shoulder. Papyrus’s magic was activating, a bulging orange glow protruding from his lower battle-body. Papyrus said nothing, but retaliated in his own way, craning his gloved hand around so that he could stimulate Blue as well. The latter’s opening had already formed, magical fluids dampening his shorts. Papyrus felt the sticky substance in his hand, and massaged the area, eliciting a shuddering moan from Blue.

 

“Hhhhold on, Pappy, I don’t want to ruin my clothes~” Blue purred.

 

“I-I’m sure Sans has something that will fit you.” Papyrus stammered out, reaching the door to his room. His eyes flashed orange, and the door knob turned, the door creaking open. Papyrus forced it the rest of the way with his foot, stepping inside with blue.

 

Papyrus locked his eyes on his bed - in any other instance he would be concerned about soiling his sheets, making a mess, being a good host, and a litany of other formalities, but the lust that radiated out of Blue had infected Papyrus to the very roots of his mind, and such thoughts were miles away.

  
Papyrus set Blue on the bed, climbing on top of him as he tore at the straps of his armor. Papyrus’s breastplate slid off, clattering against the floor as they both went for their pants.

 

Blue coaxed his shorts to his knees, fingering himself with one hand as he raised another to Papyrus’s bare shoulder blade. Papyrus’s speedo was suspended around his knees, his hands occupied as he held himself aloft with his left, stroking at his erection with his right. Orange magic dribbled out of the tip, pattering against the bedsheets. Blue’s pupils morphed into stars as he focused on the throbbing member. He rubbed against his clit in anticipation, his soiled gloves making wet sounds as it pressed against his glowing body.

 

“A-aren’t you going to get the door?” Blue asked as Papyrus bent over further, Papyrus nestling his head in Blue’s shoulder, kissing his neck.

 

“We’re fine.” Papyrus breathed. He scooted up, preparing to enter Blue.

 

“But-but what if… What if our brothers get back?” Blue asked, finding it difficult to stay focused as his feelings went wild.

 

“Trust me, this isn’t the first time this has happened. We have another hour, at least.” Papyrus pulled away, locking eyes with Blue.

 

They held eachother’s gaze, their breaths signifying their mutual anticipation.

 

Blue nodded. “I’m ready.”

 

Blue moved his hand away from his groin, reaching up towards Papyrus’s face. He held it there, centimeters away. The smell of Blue’s musk was driving Papyrus mad. He doubled back over, cradling his cheek against Blue’s soiled hand as he inserted himself.

 

The bed creaked as Papyrus thrust himself inside Blue, making deeper advances until he thrust himself to the hilt. Blue bucked as he felt his walls squeeze against Papyrus’s member, the soft sucking noises of the ample lubrication filling the air.

 

Papyrus’s tongue was exposed, his mouth open as he towered over Blue. Blue moved his soiled glove towards Papyrus’s mouth, pressing his thumb against his tongue. Papyrus tasted Blue’s fluids on his glove, his head moving to suck on Blue’s finger, savoring his lover’s juices before pulling his head back, his saliva twinged with a hint of blue magic.

 

“I thought… I thought I was supposed to be feeding you.” Papyrus quipped, leaning down onto Blue’s face. Blue’s tongue met Papyrus’s as they drew into another kiss.

 

“That’s… the dumbest thing I’ve heard you say all night.” Blue breathed, making strained giggles.

 

Papyrus made airy chuckles of his own. “Has anyone ever told you your laugh is adorable?”

 

“It’s one of my… nngh… best… traits.” Blue moaned as Papyrus’s advances brought him closer.

 

“Should I slow down?” Papyrus asked, drawing himself out of Blue, fluids leaking out of his opening.

 

Blue’s eyes widened as the sensations dulled, putting his other hand on Papyrus’s other shoulder. He drew himself closer to Papyrus and responded in a harsh whisper.

  
“ _Don’t you dare stop, I want to feel you inside my fucking stomach._ ”

 

Papyrus’s mouth hung open in disbelief. “Blue! Language!”

 

“ _S-shut up and finish what you started._ ” Blue growled.

 

Papyrus hesitated, catching his breath, before nodding. Emboldened by the primal lust that gripped his lover, Papyrus thrust himself to the hilt once more, the bones of his pelvis connecting against Blue’s inner thighs. Blue threw his head back, unable to hold back his grunts. Papyrus let out small yelps of his own as he felt himself approaching climax. His kneecaps popped as he strained them, his lower body tensing in preparation for release. Blue felt Papyrus inside him, his cock pushing against him, signaling his limit. He forced himself upwards once more, bringing Papyrus to eye level. He raised himself, holding onto Papyrus’s shoulders.

  
“Y-you’re not going to cum u-until we’re both ready, do you hear me?” Blue ordered, his voice raising above the harsh squeaking and creaking of the bed.

 

“Blue, I can’t…” Papyrus whined. Every inch of him begged to let him finish, to press harder and release the building frustration that was overflowing from inside of him.

 

“Then get me there faster!” Blue shouted, forcing his body down onto Papyrus’s cock, straining to stimulate him further.

  
“I’m, I’m trying-!” Papyrus moaned. He could feel it coming on.

 

“Just like that, Pappy, just… like…!”

 

Papyrus let out a cry, unable to contain himself any longer. Neon magic burst from the tip of his dick, pushing past the limits of Blue’s walls. Unrestrained, the fluids of Papyrus’s orgasm splattered against Blue’s spine and rib cage, the sticky orange magic hanging off his bones in strings. Blue cried in response, the pressure too much to handle. His own fluids began to spray out, coating Papyrus’s erection and ruining the bedsheets. They gripped each other as they rode the spasms of their orgasms, Blue burying his head against Papyrus’s shoulder as he whined. Papyrus’s head pushed against his mattress, making a couple final, definitive thrusts as his last spurts of cum rocketed into Blue.

 

Blue’s vision darkened, the bliss of his orgasm bringing him to the fringes of consciousness. Blue released his grips on Papyrus’s shoulders, falling back onto the bed. His intermittent gasps serving as the only indication that he hadn’t passed out.

 

“Pappy…” Blue murmured.

 

Papyrus raised himself off of the bed, staring into Blue’s face. Blue’s eyelids were heavy, drooping so that he could barely see.

  
“Yes, Blue?” Papyrus asked, brushing a hand across Blue’s cheek.

 

“C’mere.” Blue gestured with a hand, raising it like it were a lead weight.

 

Papyrus leaned in, the two skeletons locking into another kiss. Blue clasped his arms around Papyrus’s back, Papyrus wiggling a hand under Blue. Blue shifted to his side, drawing themselves closer together as they laid on the bed. They broke just long enough for Blue to murmur, “I love you.” before resuming. Papyrus broke away for a moment to breathe his reply, “I love you too.”

 

Their skulls clinked together as they wrapped themselves around one another, drifting off into blissful rest.

 

\---

 

Papyrus was the first to awaken. The sound of a door opening caused his eyelids to raise by a hair. He lumbered out of bed, taking great care to untangle himself from Blue without waking him before he made his way to the hall. From the second story he saw two skeletons get tossed without care onto the floor, each landing in an unceremonious thump. Grillby stepped in through the door, dusting his hands off.

 

“Grillby?” Papyrus asked, as the bartender looked up at him.

 

“It happened again.” Grillby stated in his usual monotone. “This is going to be put on his tab.”

 

Papyrus groaned, running a hand across his face. He looked up, alerted by the sound of footsteps from behind him.

 

“Pappy, what was tha-” Blue began, before he and Grillby noticed each other.

 

“Oh, hi Grillby!” Blue waved. Grillby’s face flared yellow. He tilted his head, rubbing the back of his neck with one hand while waving with the other.

 

“Hello, Blue. I did not know you were in town.”

 

Blue giggled, his face blushing blue. Only now did he realize his lack of pants and the plethora of orange stains that had bled through onto his shirt from his ribs.

 

“Yeah…”

 

Grillby cleared his throat. “S-sorry to bother you. Those two blacked out, so I brought them home.”

 

“Thanks, Grillby! I’ll make up for it later!” Blue said, beaming down at the bartender. Papyrus wasn’t sure what he meant by that, but based on the nod and thumbs-up Grillby responded with, he decided not to question it. Grillby took his leave, exiting the house and closing the door behind him. Stretch and Sans snored, the stench of honey and ketchup already reaching Blue and Papyrus.

 

“Well…” Papyrus began. “Looks like they won’t be up until tomorrow.”

 

Blue giggled, wrapping his arms around Papyrus’s waist. “Oh well, guess that means we’re having a sleepover.”

 

Papyrus chuckled, patting Blue against the rear. “Sorry I only have one bed.”

 

“Guess we’ll have to share~” Blue responded, giggling once more as Papyrus leaned down, clinking his skull against Blue’s.

**Author's Note:**

> This is my longest smut yet, and I am very happy with how it turned out! It was incredibly fun getting to write this pairing, because I absolutely love writing cute fluff. The interactions were very fun to write, and very organic! I hope it was enjoyable, and I'd love to answer any questions you may have about the story!


End file.
